Unity Linux 20.1050a Security Update: kernel (UTSA-2026-098741)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
##

include('compat.inc');

if (description)
{
  script_id(340447);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/08/26");

  script_cve_id("CVE-2025-38464");

  script_name(english:"Unity Linux 20.1050a Security Update: kernel (UTSA-2026-098741)");

  script_set_attribute(attribute:"synopsis", value:
"The Unity Linux host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the
UTSA-2026-098741 advisory.

    In the Linux kernel, the following vulnerability has been resolved:

    tipc: Fix use-after-free in tipc_conn_close().

    syzbot reported a null-ptr-deref in tipc_conn_close() during netns
    dismantle. [0]

    tipc_topsrv_stop() iterates tipc_net(net)->topsrv->conn_idr and calls
    tipc_conn_close() for each tipc_conn.

    The problem is that tipc_conn_close() is called after releasing the
    IDR lock.

    At the same time, there might be tipc_conn_recv_work() running and it
    could call tipc_conn_close() for the same tipc_conn and release its
    last ->kref.

    Once we release the IDR lock in tipc_topsrv_stop(), there is no
    guarantee that the tipc_conn is alive.

    Let's hold the ref before releasing the lock and put the ref after
    tipc_conn_close() in tipc_topsrv_stop().

    [0]:
    BUG: KASAN: use-after-free in tipc_conn_close+0x122/0x140 net/tipc/topsrv.c:165
    Read of size 8 at addr ffff888099305a08 by task kworker/u4:3/435

    CPU: 0 PID: 435 Comm: kworker/u4:3 Not tainted 4.19.204-syzkaller #0
    Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
    Workqueue: netns cleanup_net
    Call Trace:
     __dump_stack lib/dump_stack.c:77 [inline]
     dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
     print_address_description.cold+0x54/0x219 mm/kasan/report.c:256
     kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354
     kasan_report mm/kasan/report.c:412 [inline]
     __asan_report_load8_noabort+0x88/0x90 mm/kasan/report.c:433
     tipc_conn_close+0x122/0x140 net/tipc/topsrv.c:165
     tipc_topsrv_stop net/tipc/topsrv.c:701 [inline]
     tipc_topsrv_exit_net+0x27b/0x5c0 net/tipc/topsrv.c:722
     ops_exit_list+0xa5/0x150 net/core/net_namespace.c:153
     cleanup_net+0x3b4/0x8b0 net/core/net_namespace.c:553
     process_one_work+0x864/0x1570 kernel/workqueue.c:2153
     worker_thread+0x64c/0x1130 kernel/workqueue.c:2296
     kthread+0x33f/0x460 kernel/kthread.c:259
     ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415

    Allocated by task 23:
     kmem_cache_alloc_trace+0x12f/0x380 mm/slab.c:3625
     kmalloc include/linux/slab.h:515 [inline]
     kzalloc include/linux/slab.h:709 [inline]
     tipc_conn_alloc+0x43/0x4f0 net/tipc/topsrv.c:192
     tipc_topsrv_accept+0x1b5/0x280 net/tipc/topsrv.c:470
     process_one_work+0x864/0x1570 kernel/workqueue.c:2153
     worker_thread+0x64c/0x1130 kernel/workqueue.c:2296
     kthread+0x33f/0x460 kernel/kthread.c:259
     ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415

    Freed by task 23:
     __cache_free mm/slab.c:3503 [inline]
     kfree+0xcc/0x210 mm/slab.c:3822
     tipc_conn_kref_release net/tipc/topsrv.c:150 [inline]
     kref_put include/linux/kref.h:70 [inline]
     conn_put+0x2cd/0x3a0 net/tipc/topsrv.c:155
     process_one_work+0x864/0x1570 kernel/workqueue.c:2153
     worker_thread+0x64c/0x1130 kernel/workqueue.c:2296
     kthread+0x33f/0x460 kernel/kthread.c:259
     ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415

    The buggy address belongs to the object at ffff888099305a00
     which belongs to the cache kmalloc-512 of size 512
    The buggy address is located 8 bytes inside of
     512-byte region [ffff888099305a00, ffff888099305c00)
    The buggy address belongs to the page:
    page:ffffea000264c140 count:1 mapcount:0 mapping:ffff88813bff0940 index:0x0
    flags: 0xfff00000000100(slab)
    raw: 00fff00000000100 ffffea00028b6b88 ffffea0002cd2b08 ffff88813bff0940
    raw: 0000000000000000 ffff888099305000 0000000100000006 0000000000000000
    page dumped because: kasan: bad access detected

    Memory state around the buggy address:
     ffff888099305900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
     ffff888099305980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
    >ffff888099305a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                          ^
     ffff888099305a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
     ffff888099305b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb

Tenable has extracted the preceding description block directly from the Unity Linux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version
number.");
  # https://src.uniontech.com/#/security_advisory_detail?utsa_id=UTSA-2026-098741
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?84aef351");
  # https://lore.kernel.org/linux-cve-announce/2025072508-CVE-2025-38464-44a1@gregkh
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?fa0b9061");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2025-38464");
  script_set_attribute(attribute:"solution", value:
"Update the affected kernel package.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:S/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2025-38464");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"vuln_publication_date", value:"2025/07/25");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/08/10");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/08/26");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Unity Linux Local Security Checks");

  script_copyright(english:"This script is Copyright (C) 2026 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info2.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/UOS-Server/release", "Host/UOS-Server/rpm-list", "Host/cpu");

  exit(0);
}
include('rpm2.inc');

if (!get_kb_item('Host/local_checks_enabled')) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var os_product = get_kb_item('installed_os/local/SSH/0/product');
if (isnull(os_product) || 'UOS Server' >!< os_product) audit(AUDIT_OS_NOT, 'UOS Server');
var os_version = get_kb_item('installed_os/local/SSH/0/version');
if (isnull(os_version)) audit(AUDIT_UNKNOWN_APP_VER, 'UOS Server');
if (! preg(pattern:"^20.1050a([^0-9]|$)", string:os_version)) audit(AUDIT_OS_NOT, 'UOS Server 20.1050a', 'UOS Server ' + os_version);

if (!get_kb_item('Host/UOS-Server/rpm-list')) audit(AUDIT_PACKAGE_LIST_MISSING);

var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('aarch64' >!< cpu && 'amd64' >!< cpu && 'loongarch64' >!< cpu && 'x86_64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'UOS Server', cpu);


var constraints = [
  {
    'release': '20',
    'sp': '1050a',
    'pkgs': [
      {'reference':'kernel-4.19.0-91.82.132.24.uelc20', 'sp':'1050a', 'cpu':'aarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.0-91.82.132.24.uelc20', 'sp':'1050a', 'cpu':'amd64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.0-91.82.132.24.uelc20', 'sp':'1050a', 'cpu':'loongarch64', 'rpm_spec_vers_cmp':TRUE},
      {'reference':'kernel-4.19.0-91.82.132.24.uelc20', 'sp':'1050a', 'cpu':'x86_64', 'rpm_spec_vers_cmp':TRUE}
    ]
  }
];

var os_release = get_one_kb_item('installed_os/local/SSH/0/release');
var os_sp = get_one_kb_item('Host/*/minor_release');

var flag = 0;
var reference;
var sp;
var _cpu;
var el_string;
var rpm_spec_vers_cmp;
var epoch;
var allowmaj;
var exists_check;
var cves;
foreach var constraint ( constraints ) {
  # Check that the target release is equal to the affected release
  if (!empty_or_null(constraint['release'])){
    if (constraint['release'] != os_release) continue;
  }
  if (!empty_or_null(constraint['sp'])){
    if (constraint['sp'] != os_sp) continue;
  }
  foreach var pkg ( constraint['pkgs'] ) {
    reference = NULL;
    sp = NULL;
    _cpu = NULL;
    el_string = NULL;
    rpm_spec_vers_cmp = NULL;
    epoch = NULL;
    allowmaj = NULL;
    exists_check = NULL;
    cves = NULL;
    if (!empty_or_null(pkg['reference'])) reference = pkg['reference'];
    if (!empty_or_null(pkg['sp'])) sp = pkg['sp'];
    if (!empty_or_null(pkg['cpu'])) _cpu = pkg['cpu'];
    if (!empty_or_null(pkg['el_string'])) el_string = pkg['el_string'];
    if (!empty_or_null(pkg['rpm_spec_vers_cmp'])) rpm_spec_vers_cmp = pkg['rpm_spec_vers_cmp'];
    if (!empty_or_null(pkg['epoch'])) epoch = pkg['epoch'];
    if (!empty_or_null(pkg['allowmaj'])) allowmaj = pkg['allowmaj'];
    if (!empty_or_null(pkg['exists_check'])) exists_check = pkg['exists_check'];
    if (!empty_or_null(pkg['cves'])) cves = pkg['cves'];
    if (reference &&
        ## (no known rpm to check OR known rpm_exists)
        (!exists_check || rpm_exists(rpm:exists_check)) &&
        rpm_check(sp:sp, cpu:_cpu, reference:reference, epoch:epoch, el_string:el_string, rpm_spec_vers_cmp:rpm_spec_vers_cmp, allowmaj:allowmaj, cves:cves)) flag++;
  }
}


if (flag)
{
  security_report_v4(
      port       : 0,
      severity   : SECURITY_WARNING,
      extra      : rpm_report_get()
  );
  exit(0);
}
else
{
  var tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'kernel');
}